Method of culturing cells in a flow-through cell cultivation system

Abstract

A flow-through cell cultivation apparatus and method is described. The flow-through cell cultivation system comprises a flowcell, a chamber inside the flowcell for holding cells, and a flowcell holder. The flowcell has a lower intake port for flowing liquid nutrient through a cellbed inside the flowcell and an upper outlet port for flowing the liquid nutrient out of the flowcell. The flowcell also includes a chuck for receipt of a thermal probe. The probe is made of electromagnetically non-interactive material. The flowcell is enclosed inside the flowcell holder. The flowcell holder includes a pair of intake ports into a cavity having an open end at the flowcell for turbulently flowing a temperature controlled gas against the flowcell. The cavity has rough walls to promote the turbulent flow. The flowcell holder includes an exhaust port for flowing the gas out of the flowcell holder which also serves as a port for another thermal probe. A one-way valve prevents flow of the liquid nutrient out of the chamber through the intake port. Temperature controlled air is supplied to the flowcell holder by dividing air from an air supply into two conduits. One conduit travels through a coil inside a refrigerated liquid bath and the other through a coil inside a heated liquid bath. The heated and cooled air are recombined to make an even temperature air supply which is then divided once more to provide the two air supplies for creating a turbulent supply of temperature controlled air through the two flowcell holder intake ports. The flowcell may include on one side a semi-permeable membrane for introducing a gas/liquid interface to the cellbed.

We claim: 
     
       1. A method for cultivating cells, comprising the steps of: (a) providing a flowcell enclosing a chamber holding cells inside the flowcell, wherein the chamber has the shape of a cylindrical section about a horizontal axis;   (b) providing a flowcell holder enclosing the flowcell;   (c) flowing a liquid nutrient medium into the bottom of the flowcell chamber and out the top of the flowcell chamber;   (d) flowing a temperature controlled gas through the flowcell holder to turbulently flow against the flowcell;   (e) providing an electromagnetic field around the flowcell holder and flowcell for heating the cells; and,   (f) controlling the electromagnetic field and the temperature and flow of the gas to balance the cell heating from the electromagnetic field against the temperature and flow of the gas to maintain a preselected temperature of the cells.   
     
     
       2. A method for cultivating cells, comprising the steps of: (a) providing a flowcell enclosing a chamber holding a bed of micro-carrier beads carrying attached cells;   (b) providing a flowcell holder enclosing the flowcell;   (c) flowing a liquid nutrient medium into the bottom of the flowcell chamber and out the top of the flowcell chamber at a selected flow rate, wherein the flow rate is selected so that the micro-carrier beads are just separated and channels are not formed;   (d) flowing a temperature controlled gas through the flowcell holder to turbulently flow against the flowcell;   (e) providing an electromagnetic field around the flowcell holder and flowcell for heating the cells; and,   (f) controlling the electromagnetic field and the temperature and flow of the gas to balance the cell heating from the electromagnetic field against the temperature and flow of the gas to maintain a preselected temperature of the cells.   
     
     
       3. The method for cultivating cells according to claim 2, wherein the chamber has the shape of a cylindrical section about a horizontal axis.